The present invention relates to a suspension tower portion structure of a vehicle.
A suspension tower portion which is configured such that an upper end portion of a suspension is fixedly fastened to an upper face portion of the suspension tower portion and a rib is provided at the upper face portion, thereby improving the rigidity, in a vertical direction, of the suspension tower portion is known.
Japanese Patent Laid-Open Publication Nos. 2015-067067 or 2015-093508, for example, disclose a two-stage structure of the upper face portion of the suspension tower portion which comprises an fastening face portion for fastening the upper end portion of the suspension and a top face portion provided at a higher level than the fastening face portion and connected to the fastening face portion via a ring-shaped rib. At an upper face of the fastening face portion of the suspension tower portion is further provided a radial-shaped rib which extends in a radial direction on an outer-peripheral side of the ring-shaped rib, and the rigidity of the upper face portion is increased by the ring-shaped rib and the radial-shaped rib.
Further, plural fastening portions to which the upper end portion of the suspension is fixedly fastened are provided on the outer-peripheral side of the ring-shaped rib between the adjacent radial-shaped ribs at the fastening face portion.
Herein, since the fastening portion is provided on the outer-peripheral side of the ring-shaped rib between a pair of adjacent radial-shaped ribs as described above, a distance between a peripheral portion of a fastening seat portion at the fastening portion and the radial-shaped rib is not constant. Accordingly, the rigidity of a portion around the fastening portion does not become uniform, so that there is a case in which a stress which is generated by a load inputted in the vertical direction from the suspension may not become constant at a peripheral portion of a fastening seat face and thus the stress may concentrate locally.
That is, there is room for further improvement in the rigidity, in the vertical direction, of the suspension tower portion from stand points of suppressing local stress concentration at the fastening portion.